Recently, portable radio communication devices including a radio communication function have been widely used. The radio communication device can perform radio communication with other radio communication devices by directly transmitting/receiving radio signals to/from another radio communication device, for example. Radio communication by such radio communication device sometimes is referred to as an ad-hoc mode in comparison with an infrastructure mode which requires a base station.
Further, when a radio communication device on transmitting side transmits a packet (data) to a radio communication device on receiving side by radio, the packet is sometimes lost and the other radio communication device cannot receive the packet properly. In order to solve the issue due to a packet loss, Qos (Quality Of Service) such as an FEC (Forward Error Correction), an ARQ (Automatic Repeat Request) and the like have been proposed.
The FEC is a technology for recovering a lost packet by redundant coding. The radio communication device on transmitting side generates a redundant packet (parity packet) based on a transmission packet and adds the redundant packet to the transmission packet, so the radio communication device on receiving side can recover the lost packet by decoding the transmission packet using the redundant packet.
Further, the ARQ is a technology for recovering a lost packet in which the lost packet detected in the radio communication device on receiving side is informed to the radio communication device on transmitting side and the radio communication device on the transmitting side retransmits the lost packet. The Qos including FEC, ARQ and the like are described in Patent Literature 1, for example.